INFO: task syz.2.888:8811 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.888 state:D stack:21896 pid:8811 ppid:5760 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6700
schedule+0xbd/0x170 kernel/sched/core.c:6774
perf_pending_task_sync kernel/events/core.c:5242 [inline]
_free_event+0x174/0xf30 kernel/events/core.c:5248
put_event kernel/events/core.c:5376 [inline]
perf_event_release_kernel+0x836/0x8c0 kernel/events/core.c:5501
perf_release+0x3b/0x40 kernel/events/core.c:5511
__fput+0x234/0x970 fs/file_table.c:384
task_work_run+0x1ce/0x250 kernel/task_work.c:245
get_signal+0x1235/0x1400 kernel/signal.c:2678
arch_do_signal_or_restart+0x9c/0x7b0 arch/x86/kernel/signal.c:310
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xf6/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f123138f749
RSP: 002b:00007f1232274fe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: fffffffffffffffc RBX: 00007f12315e5fa0 RCX: 00007f123138f749
RDX: 0000200000000140 RSI: 0000200000000300 RDI: 00000000c0840000
RBP: 00007f1231413f91 R08: 00002000000003c0 R09: 00002000000003c0
R10: 0000200000000240 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f12315e6038 R14: 00007f12315e5fa0 R15: 00007ffe73551af8
Showing all locks held in the system:
1 lock held by rcu_tasks_trace/15:
#0: ffff8880b8f3c018 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:559
1 lock held by khungtaskd/29:
#0: ffffffff8cd2ffa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#0: ffffffff8cd2ffa0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#0: ffffffff8cd2ffa0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
2 locks held by getty/5523:
#0: ffff88803142a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000326e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217
2 locks held by syz.5.1477/11360:
3 locks held by syz.5.1477/11382:
4 locks held by syz.6.1492/11395:
2 locks held by syz.5.1491/11411:
#0: ffffffff8cd85f28 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2e/0x140 kernel/trace/trace_event_perf.c:239
#1: ffffffff8cd35978 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:292 [inline]
#1: ffffffff8cd35978 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x448/0x830 kernel/rcu/tree_exp.h:1004
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 29 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x39b/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
watchdog+0xf41/0xf80 kernel/hung_task.c:379
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 11395 Comm: syz.6.1492 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:182 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x10/0x60 kernel/kcov.c:216
Code: 89 fb e8 13 00 00 00 48 8b 3d 1c 91 c4 0c 48 89 de 5b e9 13 9f 56 00 cc cc cc f3 0f 1e fa 48 8b 04 24 65 48 8b 0d b0 0a 7e 7e <65> 8b 15 b1 0a 7e 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75
RSP: 0018:ffffc90000007508 EFLAGS: 00000082
RAX: ffffffff813acf79 RBX: ffffffff8edd5137 RCX: ffff88802b603c00
RDX: ffffc900000076e0 RSI: ffffc9000bb97340 RDI: ffffc900000076a0
RBP: dffffc0000000000 R08: ffff88802b603c00 R09: 0000000000000003
R10: 0000000000000004 R11: 0000000000010000 R12: ffffc900000076a0
R13: dffffc0000000000 R14: ffffffff8edd5136 R15: ffffc900000076a0
FS: 00007faa37b026c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe53d9b7198 CR3: 000000001bf79000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000200000000300
DR3: 0000200000000300 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
deref_stack_reg+0x29/0x240 arch/x86/kernel/unwind_orc.c:402
unwind_next_frame+0x1789/0x2970 arch/x86/kernel/unwind_orc.c:648
perf_callchain_kernel+0x3a8/0x5f0 arch/x86/events/core.c:2780
get_perf_callchain+0x223/0x4d0 kernel/events/callchain.c:204
perf_callchain kernel/events/core.c:7740 [inline]
perf_sample_save_callchain include/linux/perf_event.h:1232 [inline]
perf_prepare_sample+0x3a2/0x1d20 kernel/events/core.c:7784
__perf_event_output kernel/events/core.c:7972 [inline]
perf_event_output_forward+0x152/0x3a0 kernel/events/core.c:7993
__perf_event_overflow+0x447/0x630 kernel/events/core.c:9718
perf_swevent_hrtimer+0x3bc/0x530 kernel/events/core.c:11188
__run_hrtimer kernel/time/hrtimer.c:1750 [inline]
__hrtimer_run_queues+0x4df/0xc40 kernel/time/hrtimer.c:1814
hrtimer_interrupt+0x3c9/0x9c0 kernel/time/hrtimer.c:1876
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1077 [inline]
__sysvec_apic_timer_interrupt+0xfb/0x3b0 arch/x86/kernel/apic/apic.c:1094
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1088
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:60 [inline]
RIP: 0010:unwind_next_frame+0x1cc6/0x2970 arch/x86/kernel/unwind_orc.c:665
Code: 3c 28 00 74 08 4c 89 ff e8 27 5b a2 00 49 8b 07 4c 39 f3 0f 96 c1 4c 39 f0 0f 97 c2 84 d1 74 3c 49 8d 4e 08 48 39 d9 0f 96 c2 <48> 39 c1 0f 97 c0 49 39 ee 0f 97 c3 08 c3 08 d3 4c 89 f7 48 89 ee
RSP: 0018:ffffc9000bb96b18 EFLAGS: 00000202
RAX: ffffc9000bb98000 RBX: ffffc9000bb90000 RCX: ffffc9000bb977a8
RDX: ffff88802b603c00 RSI: 0000000000000001 RDI: ffffc9000bb96bf0
RBP: ffffc9000bb97680 R08: ffff88802b603c00 R09: 0000000000000003
R10: 0000000000000004 R11: 0000000000000002 R12: ffffc9000bb96be8
R13: dffffc0000000000 R14: ffffc9000bb977a0 R15: ffffc9000bb96bf8
arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:46 [inline]
kasan_set_track+0x4e/0x70 mm/kasan/common.c:53
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:329
kasan_slab_alloc include/linux/kasan.h:188 [inline]
slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767
slab_alloc_node mm/slub.c:3495 [inline]
slab_alloc mm/slub.c:3503 [inline]
__kmem_cache_alloc_lru mm/slub.c:3510 [inline]
kmem_cache_alloc+0x11e/0x2e0 mm/slub.c:3519
kmem_cache_zalloc include/linux/slab.h:711 [inline]
__kernfs_new_node+0xd8/0x7e0 fs/kernfs/dir.c:624
kernfs_new_node+0x14c/0x260 fs/kernfs/dir.c:700
__kernfs_create_file+0x4b/0x2e0 fs/kernfs/file.c:1068
sysfs_add_file_mode_ns+0x238/0x300 fs/sysfs/file.c:294
sysfs_merge_group+0x178/0x310 fs/sysfs/group.c:346
dpm_sysfs_add+0xd2/0x270 drivers/base/power/sysfs.c:707
device_add+0x56a/0xc20 drivers/base/core.c:3643
netdev_register_kobject+0x17a/0x310 net/core/net-sysfs.c:2042
register_netdevice+0x128f/0x1ae0 net/core/dev.c:10311
__ip_tunnel_create+0x3b4/0x4c0 net/ipv4/ip_tunnel.c:267
ip_tunnel_init_net+0x2c3/0x770 net/ipv4/ip_tunnel.c:1104
ops_init+0x397/0x640 net/core/net_namespace.c:139
setup_net+0x3a5/0xa00 net/core/net_namespace.c:343
copy_net_ns+0x36d/0x5e0 net/core/net_namespace.c:520
create_new_namespaces+0x3d3/0x6f0 kernel/nsproxy.c:110
copy_namespaces+0x430/0x4a0 kernel/nsproxy.c:179
copy_process+0x1700/0x3d70 kernel/fork.c:2509
kernel_clone+0x21b/0x840 kernel/fork.c:2914
__do_sys_clone kernel/fork.c:3057 [inline]
__se_sys_clone kernel/fork.c:3041 [inline]
__x64_sys_clone+0x18c/0x1e0 kernel/fork.c:3041
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7faa36b8f749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007faa37b01fe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007faa36de5fa0 RCX: 00007faa36b8f749
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000042164000
RBP: 00007faa36c13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007faa36de6038 R14: 00007faa36de5fa0 R15: 00007ffda6c4c2d8